Burglar-alarm



(No Model.)

T. H. LOVELL 86 G. BUGKINGHAM. BURGLAB. ALARM.

No. 493,037. Patented Mar. '7, 1893.

UNITED STATES PATENT OFFICE.

THOMAS H. LOVELL AND GEORGE BUOKINGI-IAM, OF CLEVELAND, OHIO.

BURG LAR-ALARM.

SPECIFICATION forming part of Letters Patent No. 493,037, dated March 7,1893.

Application filed July 22, 1892.

To all whom it may concern.-

Be it known that we, THOMAS H. LovELL, a subject of the Queen of GreatBritain, and GEORGE BUCKINGHAM, a citizen of the United States, andresidents of Cleveland, county of Cuyahoga, State of Ohio, have inventedcertain new and useful Improvements in Burglar-Alarms, of which wehereby declare the following to be a full, clear, and exact description,such as will enable others skilled in the art to which it appertains tomake and use the same.

Our invention relates to improvements in automatic burglar alarms, andit is designed to be attached to a window or door by the occupant of theroom from the inside, so as to prevent anyintrusion without the reportfollowing of a detonating cap or cartridge.

Our invention consists in the combination and arrangement of parts andconstruction of details as hereinafter described shown in theaccompanying drawings and more particularly pointed out in the claims.

In the drawings, Figure l is a perspective view of the device attachedto a windowframe. Fig. 2 is a form of device adapted to be attached to adoor. Fig.3 is a view of the separated details; and Fig. 4 is a detailof door plate, and Fig. 5 a modified detail.

A in the drawings is a case provided with hollow projection A inclosin gthe hammer rod or bar B, one side of the case at a being open for itsadmission. A plate H serves to retain the rod Bin position and isprovided with guiding lugs h against which the rod rests. Small lugs Iupon the case A retain the plate H. A pin 1) projects from the rod B,and passes through the slot E, in the case A, the upper end of this slotis extended at right angles thereto as at e e and a spring 0 is sleevedover the rod B within the cavity of the case. Openings at and a in thecase admit the hammer B. A platform is placed at D, against which therod B rests when not in use.

In operation when in use on a window frame the case A is fixed by screwsin the perforations a to the casing, and the rod B drawn up against thespring 0 until the pin 17 can be turned into the cross e e of the slot sal Na 440,942. (No model.)

E where it sustains the rod B. Upon the window frame is placed thedoubly beveled angle plate F secured at f in such a position that thebeveled surfaces will engage the pin b and throw it back into the slotE, if the window be raised or lowered so as to push the plate F past thecase A. In this case the moment the rod B is released the spring willthrow it with great forceagainstthe platform D, upon which thedetonating cap is placed. The loud explosion which follows is sufficientto arouse the inmate of the room even if asleep. When a blank cartridgeis used the platform D is drilled to receive it.

G is an angular plate to which the case A may be secured when it isdesired to attach the device to a door. It will be seen that the plateis passed between the edge of the door and jamb where it is held bypressure and by the smaller lugs g, g, which enter the jamb and preventslipping, when the dooris opened.

It will be seen that the case is somewhat inclined toward the door sothat when the door is opened the edge will strike the pin, 1) and throwdown the rod B against the platform and cap.

In use with the door the construction need not be different from thatshown, as adapted to a window. When used with the window frame it may beplaced at any position on the frame near the top or bottom so that, thewindow may be left open slightly at the top or bottom and sound thealarm if pushed farther than enough for ventilation. The plate G couldbe adapted to use with a loose window. 7

Having described our invention, what we claim as new, and desire tosecure by Letters Patent, is

1. In a burglar alarm, a plate G, provided with a bent over extremityand lugs g g whereby the plate may be secured between a door and itsframe, in combination with a metallic case A inclosing a spring actuatedhammer B, provided with a pin b the said case being secured to the bentover portion of the plate G, in such a position as to cause the pin tobe struck and the hammer released when the door is opened, substantiallyas set forth.

2. In a burglar alarm the combination of the case A provided withastriking platform the pin and release the hammer when the and detonatingcap or cartridge, a spring actdoor is opened, as and in the manner setforth. 1o mated hammer B within the case provided with a pin b, with abent plate G,seoured rig- THOMAS H. LOVELL.

5 idly to said case Aand provided with lugsb b GEORGE BUOKINGIIAM.

and adapted to be retained by pressure be- Witnesses: tween the edge ofthe door and ease in such WM. M. MONROE,

a position that the edge of the door will strike MARY P. SPARGO FRASER.

